Helper: Use QStringLiteral

src/Workflow/Helper.cpp

@@ -26,7 +26,7 @@ using namespace Workflow;
 
 Helper::Helper( const QString &uuid/* = QString()*/ )
 {
-    if ( uuid.isNull() == true )
+    if ( uuid.isEmpty() == true )
         m_uuid = QUuid::createUuid();
     else
         m_uuid = uuid;

src/Workflow/Helper.h

@@ -34,7 +34,7 @@ namespace   Workflow
         Q_OBJECT
 
         protected: //This class is not meant to be used by itself.
-            Helper( const QString &uuid = QString() );
+            Helper( const QString &uuid = QStringLiteral() );
             ~Helper();
 
         public: